Frank Fernandez’s family never stays in one place for long. His parents renovate unusual buildings and turn them into homes, which means the family moves—a lot. This makes it hard for bookish Frank to make friends. So when his parents announce they’re moving to Spectacle Key, Florida, to live in a lighthouse—this time for good!—Frank is thrilled. But Spectacle Key isn’t the perfect forever home they'd imagined. The lighthouse is falling apart. There are knocks on the door—but no one is there—and mysterious sighs and sniffles from nowhere. There’s even a creepy doll that seems to move on its own. Could Spectacle Key be haunted?

Then one day while exploring, Frank meets a girl in old-fashioned clothes, with no memory of who she is. What she does know, though, is that the island is under a curse—and she needs Frank’s help to figure out how to lift it. But what if learning the truth about Spectacle Key means losing the first real friend he’s ever had?